An email or portions of an email may be received in a HyperText Markup Language (HTML) format. Conventional systems, when rendering the email, render portions twice. The email may first be rendered with styles or scripts that are included in the HTML email. When rendering the email, external content such as images may be downloaded. After retrieving all the content and rendering the email once, the system may apply a custom style or script to the HTML email, and the email may be rendered a second time with the system's desired formatting. The external content may be downloaded a second time as well. Rendering twice and downloading external content twice is inefficient. Further, displaying the email both times that it is rendered may present a flickering effect or changing the display to a user. Similar problems are encountered with non-email content as well.